Improved frjctional electric machine



R. CORNELIUS. FRIGTIONAL ELEGTRIG MACHINE.

No. 32,354. Patented May 21, 1861.

f w nny @la/ @WM UNITED STATES PATENT OFFICE.

lMPROVED FRICTIONAL ELECTRIC MACHINE.

Specification forming part of Letters Patent No. 32,354, dated May 21,1861.

To all whom 'it may concern.-

Be it known that l, ROBERT CORNELIUS, of Philadelphia, in the State ofPennsylvania, have made certain new and useful Improvements in theConstruction of Electric Generators; and I do hereby declare thefollowing to be a full, clear, and. exact description of the same,reference being bad to the annexed drawings, making a part of thisspecification, in which- Figures 1 and 2 represent the outside views ofthe sides; Fig. 3, an end View; Figs.4 and 5, inside views correspondingto Figs. 1 and 2; Fig. 6, a sectional view, showing the interiorarrangement; Figs. Tand 9, two views of the a detached boxes; Fig. 8,adetached view of the revolving disk; Fig.16, a detached view of theccllector.

Heretcfore electric generators of small size have been composed ofarevolving disk of some non-conducting material inclosed in anoncondncting case; but there were certain defects in. the constructionof these electric'generators which have seriously impaired theirpractical value and efi iciency. In the first place, the leather whichpresses against the revolving disk being inclosed entirely in the case,it was impossible to adjust it to the disk without taking the apparatusto pieces, and even then it could not be eflectually done, as theputting of the parts together would change the adjustment. Again, therubbers have been heretofore made of leather and placed upon a metallicbase and pressed against the disk by a spring. The rubber, in time, bythecontinual pressure of the leather between the metal back and thedisk, causes its surface to become hard and unyielding, therebyimpairing its efficacy as an exciter of electricity. Much inconveniencehas hitherto been' experienced from the want of a complete adjustingarrangement and an efficient'rubber in these inclosed electricgenerators.

My improvement consists, first, in so constructing these electricgenerators inclosed in cases that the rubber is connected externallywith the spring and with the adjusting apparatus, or with either,instead of having these parts inclosed within the case; secondly, inconstructing the rubber with an elastic backing, of leather or cloth,having a tin or metallie foil interposed between the leather and thepacking, whereby the full elasticity of the rubher is maintained, and atthe same time its efficacy as a generator of electricity is retained bythe employment of the metal foil; thirdly, in a convenient mode or"inclosing the cushion and its packing in the recess in the case or boxinserted in the case; fourthly, in an improved arrangement of spring andadjusting-screw for maintaining a uniform and regular pressure of "therubber upon the revolving disk in the case.

I have also found that by placing a series of grooves around eachsurface of the dish its action in generating electricity is more promptat the first start.

The electric generator is constructed as follows: A disk, A, of hardrubber or other nonconducting material, is put upon an axis, B, attachedto which is a handle, G. The disk A is surrounded by a case, D I), madeof hard rubber or other non-conducting substance.

E are the rubbers, pressing on each side of the revolving disk A. Theyare made of a piece of soft leather fastened to the outer casing, 1) D,by their edges. An opening is made through the casing over this leather,in which metallic cups 9 it are placed.

In order that the rubbers may be pressed firmly against the revolvingdisk, 2. spring, 7;,

presses firmly against the cup g, which, in its turn, presses theleather against the disk. The opposite rubber is pressed tightly againstthe diskby means of the cup h, which is provided with a screw by meansof which it may be screwed in and out. If these cups were solid metal,the leather would soon become hard. To obviate this difiiculty I fillthe cups with cloth, rubber, or other soft substancaand between thisfilling and the leather I place a small piece of metallic foil. Thismetallic foil is in contact with the metal cup, and thus the rubberpreserves the quality necessary to excite electricity, while atthesametime its elasticity is improved. The electricity thus generatedis collected upon the collector 0, (shown in Fig. 10.) This is of theform shown in the figure, and slidesin the grooves p p on the case,Figs. 4 and 5.

It is seen that the spring is causes the press are of the rubbers to beuniform.

A spring might be attached to both rubbers,

or each cup might be provided with a screw and sewed against the disk.

Should the rubber be too loose or too tight, it is easily regulated bymeans of screwing the cup in or out.

By corrugating the disk A the rubber will press more firmly against it,and electricity would be more easily generated.

Having thus described my improvement, what I claim as my invention, anddesire to secure by Letters Patents, is

1. Applying the spring or adj usting-screw to the rubber outside ofthe-case and bringing the same into action through the case.

2. The employment of the elastic backing for the rubber, in combinationwith the metallic foil placed between the back of the rubber and elasticcushion.

3. The placing of the elastic cushion in a recess of the case or in ametallic box made to lit in arecess in the case.

ROBERT CORNELIUS.

Witnesses J. G. MINE CHILD,

F. D. BOQUET.

